1. Field of the Invention
The present invention relates to an ink jet recording apparatus. More particularly, the invention relates to an ink jet recording apparatus having improved means for conveying sheets.
2. Related Background Art
As a recording apparatus, the so-called serial type recording apparatus has hitherto been used widely. As shown in FIG. 8, this apparatus is provided with a recording head 101 having discharge ports provided at a lower side thereof for discharging ink onto a recording sheet 102 downward substantially in the vertical direction and executes recording for one line after another, for example, by moving the head in the reverse and forward directions in FIG. 8 and then, conveys the recording sheet 102 by one line in the right-hand direction in FIG. 8 for recording the next line.
In such a recording apparatus, the recording sheet 102 is pressed by a pinch roller 104 to a feed roller 103. The recording sheet 102 closely in contact with the feed roller 103 is conveyed in the right-hand direction in FIG. 8 by the rotation of the feed roller 103 by driving means which is not shown.
Also, in the right-hand direction of the recording sheet 102, a sheet exhausting roller 105 and a spur 106 are arranged. The spur 106 is biased by a spur spring 107 to press the recording sheet 102 to the sheet exhausting roller 105. By the conveyance by the sheet exhausting roller 105, the recording sheet 102 is conveyed without slackening in a portion opposed to the recording head 101. On the trailing end thereof, the sheet exhausting,operation is performed so that the sheet falls into a sheet exhausting stacker 108.
However, according to the above-mentioned prior art, a problem is encountered that a leading end of the recording sheet 102 which is being currently printed rubs the printed surface of the recording sheet which has already been exhausted as shown in FIG. 9 so that the recording sheet 102 may be contaminated by ink in some cases.
Also, as shown in FIG. 10, there are problems that the trailing end of the recording sheet 102 leaping up when it is exhausted may be in contact with the discharge port surface of the recording head 101 so that the recording sheet 102 is contaminated. In addition, in some cases, defective discharges may occur because the discharge ports are damaged or dust particles are adhered to them. In order to solve these problems, it is conceivable that the recording head 101 is arranged to move out of the recording area when the recording sheet is exhausted. In this case, however, no recording operation is possible once the recording sheet has left the feed roller 103 and the pinch roller 104. Therefore, another problem is encountered that the recordable area should become narrower inevitably.
The present invention is designed to solve these problems. It is an object of the invention to provide an ink jet recording apparatus capable of preventing the leading end of the subsequently fed recording sheet from being caused to stain the printed recording sheet, and also, preventing the trailing end of the recording sheet from being in contact with the recording head.
In order to achieve the object, the present invention provides an ink jet recording apparatus comprising: a recording area where a recording sheet is conveyed substantially in a horizontal direction to a position opposite to a discharge port for discharging ink, and recording is performed by discharging ink from said discharge port downward substantially in a vertical direction to said recording sheet; and a sheet-exhausting area where said recording sheet is conveyed from said recording area and exhausted, said sheet-exhausting area having first sheet conveying means for introducing said recording sheet from said recording area to said sheet-exhausting area and second sheet conveying means for holding said recording sheet introduced from said recording area to said sheet-exhausting area by said first sheet conveying means substantially in the horizontal direction or above the substantially horizontal direction and exhausting said recording sheet substantially in the horizontal direction or above the substantially horizontal direction.
As stated above, the following advantages are obtained by arrangements of the embodiments showing such as an arrangement that second means for conveying a sheet for exhausting the recording sheet is provided at a position on an extended surface of the sheet conveyance route or deviated to a printing surface or upward in the vertical direction with respect to the extended surface.
(1) it is possible to delay the period of time in which the leading end of a current recording sheet is caused to contact the recorded surface of the sheet already exhausted, thus preventing ink stains from being generated; and
(2) the rear end of the recording sheet can be prevented from leaping up when it is exhausted, thus enabling the recording operation to be executed even after the recording sheet is out of the feed roller and pinch roller and obtaining a wide recordable area.
Hereinafter, in conjunction with the accompanying drawings, the detailed description will be made of the embodiments according to the present invention.